Structural Biology is a new AECCC shared resource that provides atomic resolution information on structure, function, and mechanisms of macromolecules. The three components include: structural NMR, rotating anode crystallography, and synchrotron crystallography. This is supported by molecular modeling and graphics resources and >30 SGI workstations. The structural NMR component is housed in a new facility opened December 1996 with new 600 MHZ and 300 MHZ spectrometers. This facility will also utilize 800 MHz spectrometers in Manhattan that will be operated by a consortium of the College and other New York Institutions. NMR data are processed and analyzed on five offline UNIX workstations that are also used for the calculation, simulation and visualization of molecular structures. NMR data processing, molecular simulation, and molecular graphics programs are provided. Crystallography equipment includes Rigaku RU200 and RU300 rotating anodes and Siemens X1000 and High Star Area Detectors. This was recently upgraded with an R-Axis IV++ image plate detector, new generator and associated optics (RU300). Synchrotron services are provided by beamlines assigned to the College at the National Synchrotron Research Laboratory at Brookhaven, Long Island. The College owns a share of the X9-B beam in partnership with NCI. AECCC utilization of this line is increasing and was 46 days in 1999. The X-9A line will become operational fall 2000; the College owns a 1/3rd share of this beamline in partnership with Rockefeller University and Sloan Kettering. This will provide >60 additional days of beam-time/year, most of which will be allocated to AECCC investigators. Each beamline is equipped with sagittal focusing monochromators and vertical focusing mirrors for high-flux bending magnet work. Both have cryogenic cooling and CCD detection available for macromolecular crystallography. X-rays are tunable from 5-15 keV, under normal operating configurations, suitable for accessing the most common MAD elements. The Structural Biology Shared Resource provides multiple services for AECCC investigators. These include, but are not limited to, assistance in planning appropriate experiments, aligning/calibrating instruments, and setting up experiments for unassisted operation. The staff will run experiments for users, troubleshoot or "call-in" during "off-hours" operation, and provide training in the use of instruments and data analysis. Since 1996 the facility has received $4.0M in support for capital equipment from Federal agencies (i.e. SIG) and foundations, and matching funds from the College or other institutional partners. In addition, the College currently provides approximately $300,000/year of support for operations.